Well, since you've already sent your Leica gear off and ordered the digicam I suppose its a bit too late to comment. However, I think its the old toss-up between quality and convenience. The digicam will be more convenien t and easy, but the same quality won't be there.
However, for my 2 cents... Since I'm in the film biz I have quite a few buddies who are cinematographers/ lighting cameramen, and know of quite a few more. None of them have digital equipment, or even think that digital will replace 35mm as the standard feature film stock in the next 5-10 years or so. All of them have Leicas though, funnily enough. One of them recently wrapped on Harry Potter, the other on The Corpse Bride.
Think about that for a moment. Firstly, 35mm is the cinema standard, not 70mm, and its still considered sharp enough to blow up on a huge cinema screen. Secondly, both of those are special effects heavy movies (therefore much more convenient to shoot them on HDCAM SR, or one of the other high definition video formats (the feature I'm editing right now was shot on HDCAM, but that was for cost reasons, not quality). Hollywood spends a lot of money on film stock, when HD stock is relatively very very cheap, and yo u can bet your ass if they felt they could lose that spend, they'd drop 35mm film like a hot cake. Lucas obviously felt that the compromise was worth it when he shot the last two Star Wars on HDCAM SR, but that was because those films are almost entirely digital domain (all the backgrounds, everything) the actors are shot bluescreen the whole way through.
Now, the Corpse Bride guy was particularly interesting (I know his father who told me this, in this case, not him personally, in case he reads this forum and thinks 'who?') because its composed of images taken with stills cameras and its the only instance I know about where they did side by side comparisons between film and digital stills cameras to find out what the cost/quality tradeoff was. They picked the best digital, and stills SLRs and, under the same lighting conditions of the same scene, tested them. The film and digital prints were then handled with the optimum quality in mind and they projected them. Apparently, 35mm was still quite clearly better in quality once blown up on a cinema screen (particularly in shadow-detail according to the expert eyes assessing this). However, they ended up shooting with Digital SLRs for cost reasons, because it was considered that although film was ultimately better, that Joe Public wouldn't discern enoug h of a difference to warrant the extra cost of film being used for the animation. I don't know about you, but I rarely find what Joe Public thinks is marvellous very good quality wise (in the 80s, VHS camcorders replaced Super 8mm in the public's eyes, for goodness sake! have you ever seen VHS camcorder footage, its shockingly bad - Super 8mm is wonderful even compare d to modern consumer DV).
I also recently went into a good photographic centre near me (before I decided to stay 35mm and get a Leica) and asked them to show me the best digital prints they had (done on a £60,000 printer - how many films could you develop and print before buying one of those?), mixed in with 35mm prints, without telling me which were which. It didn't take me long, and it was very easy! Have you ever done this? There is always 'noise' of some kin d on even the 'best' digital prints I've ever seen. They look initially impressive (IMO reduced shadow detail and tonal information makes them look more contrasty) but let your eye adjust and you'll see the difference.
So take that as you will. Personally because I'm used to evaluating images fairly closely as an editor, I can tell you that I've yet to see any digita l stills or motion footage that can match good 35mm. The other issue is printing, to get the best quality you have to take those digital pics to a place with a very good, very expensive printer to get anywhere near 35mm, s o you won't be printing at home, which kind of negates the cost-saving of going digital to start with?
However, I hope you enjoy your digital experience and aren't dissapointed with it after using such good 35mm.
All the best, James